Engineers started to make the walls lower, much thicker and slightly angled inwards.
Stone was partially replaced by brick and earth.
These new low walls were better at deflecting and absorbing gunshots.
The lower height had the disadvantage of making the walls more vulnerable to old-fashioned infantry attack.
Therefore ditches in front of the walls were widened and deepened.
The pattern of the walls became star-shaped.
This allowed defenders to fire upon attackers who tried to assault the walls from two flanks,
spraying bullets all over their lines in what is called an enfilade.
The forts were further enhanced by structures like ravelins and redoubts, which extended or shielded the main structure.
Some forts extended the defensive inwards, putting up two or even three rings inside each other,
similar to a concentric castle.
The first star forts were developed in the mid 15th century CE in Italy and from there spread all over Europe.
The skills of fortress-building engineers like the Italian pioneers, the Dutch and the Frenchman Vauban were highly prized.
Star forts re-established the importance of static defenses.
They shifted the emphasis from field battles, which had reigned for about a century, to back to sieges.
But never again would fortifications become as important as the castles of the Middle Ages.
War Matrix - Star fort
Late Middle Age 1300 CE - 1480 CE, Weapons and technology